W3L2 - Macromolecules II - Proteins

Question 1

What is the structure of proteins

Answer 1

polymers (many molecules) of amino acid monomers

Question 2

What are the polymers of amino acids also referred to as

Answer 2

polypeptides

Question 3

How are amino acids linked together

Answer 3

by peptide bonds

Question 4

Describe the primary structure of a protein

Answer 4

Long linear sequence of amino acids joined by peptide bonds

Question 5

what are the two major elements of a secondary protein

Answer 5

alpha-helix and beta strand

Question 6

What do bonds do secondary proteins have?

Answer 6

hydrogen bonding

Question 7

What are the regions that allow changes in the direction of the polypeptide chain

Answer 7

turns and loops

Question 8

Why do you need turn and loops within a protein

Answer 8

proper folding determines how a protein works in the body

Question 9

In what directions can beta sheets in secondary structures form

Answer 9

parallel and anti-parallel

Question 10

What are the weak interactions that contribute to the structure of the tertiary protein

Answer 10

hydrophobic interaction, hydrogen bonding, ionic bonds

Question 11

If the tertiary protein has these weak interactions why is the overall protein still strong

Answer 11

individually the forces are weak but when combined together they form an overall strong structure

Question 12

What are the strongest bonds within a tertiary protein structure

Answer 12

disulfide bridges

Question 13

What is the feature of a fibrous 3D protein structures (tertiary) protein structure?

Answer 13

long, rod-like, insoluble in water, mostly alpha-helices

Question 14

What are examples of fibrous 3D protein structures?

Answer 14

collagen (tendons, ligaments), fibroin (spider silk), keratin (hair, nails), fibrin (blood clot)

Question 15

Explain the features of a globular 3D protein structures

Answer 15

compact + fold back on themselves, usually soluble, complex structures, both alpha-helices and beta sheets

Question 16

Examples of a globular 3D protein structures

Answer 16

haemoglobin

Question 17

What is the structure of quaternary protein structures

Answer 17

consisting of more than one polypeptide chain

Question 18

What is protein denaturation

Answer 18

conditions (pH/heat) → disrupt secondary/tertiary structure of a protein → lose function

Question 19

What is the function of enzymatic proteins

Answer 19

selective acceleration of chemical reactions

Question 20

What is an example of enzymatic proteins

Answer 20

digestive enzymes catalyse the hydrolysis of bonds in food molecules (break down)

Question 21

What is the primary function of proteins

Answer 21

enzymal activity